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- CFD Modelling of 3D Effects in Cycloidal RotorsPublication . Rami, Mehdi Habibnia; Marques, José Carlos PáscoaThe cycloidalrotor (cyclorotor) is a revolutionary propulsion system that has not been systematically studied in the past in terms of its different aspects and applications. Therefore, the current research presents the viability of the cyclorotor concept for powering a hoveringcapable unmanned scale aerial vehicle (UAV) through both computational fluid dynamics (CFD) and also artificial neural network (ANN) analysis. Numerical or CFD simulations included both performance and flow field measurements on a cyclorotor of span and diameter equal to 0.8 meter. The simulations consist of diverse operating conditions and under various flight phases. Hovering capabilities, forwardflight and liftup phases, operating under at closeground flight levels, and threedimensional (3D) effects of the endplates in the sides of cyclorotor in this scale. Furthermore, a novel propulsion system by using a coupled combination of two cyclorotors and pairwing system by using plasma actuators is also presented in the current study as a recent patent. Numerous simulations for various types of flight strategies and operating conditions are performed and recorded as a database from the CFD phase. Subsequently, all the data from the numerical computations are processed in ANN algorithms for further analysis and optimizations for all of the assessed operating conditions in all modes. The ANN analysis could effectively propose an optimal condition for all the abovementioned operations on the basis of the loading parameters, force coefficients, and figure of merit for efficiency analysis. The operating conditions in the current study refers to the ranged of pitching oscillation angles, and rotation speed, and the flight mode defines the different flying regimes such as hovering, closeground, or liftup and forwardflight concepts. Systematic and aerodynamic performance measurements and analysis have been conducted to understand the effect of the rotational speed, blade pitching amplitude, pitching axis location, forward/cruise speed, takeoff speed, different ground heightlevels. Force measurements showed to be distinctive in different regions on the circular trace of the traversing blades. The NACA 0012 profile is considered constantly for all the simulations in the current work. On the basis of ANN analysis, an active control methodology, meaning that smart pitching schedules are proposed for each of the operating conditions, that results in higher aerodynamic performance and efficiency augmentation. This happens by keeping the cycloidal definition in these rotor types, but instead of running the blades in a constant schedule over cycles, we proposed an alternative varying pitch schedule in accordance to the blade position which is called azimuth angle. This revealed significant enhancement in the overall cyclorotor efficiency at each flight mode and operating condition. Concerning the attraction of downwash jet flow from the bottom region of the cyclorotors, the present patent illustrates to guide the downwash jet through a nozzle duct which is consisted of double wings in the middle of two cyclorotors in the front and rear part of the propulsion mechanism. Thus, instead of washing away the downwash jet, we process it and make a possible running flow to face the rear rotor which operates at higher angular velocities and smaller scale compared with that of front cyclorotor.